Filtering product data in sidebar


I'm developing a clothing store and want to be able to filter the data
(in a sidebar) by category, brand, styles etc. I see other (mainly
php) sites doing this by appending to the url eg
&brand=adidas&category=shorts etc. but not sure if this is the way to
go or if rails provides a better way.

What is an effective way of doing this in Rails? Some tips and links
would be appreciated.